Method and apparatus for pressure working materials

ABSTRACT

A METHOD AND APPARATUS ARE PROVIDED FOR FORMING MATERIAL SUCH AS SHEETS AND PLATES BY MEANS OF INTENSE PRESSURE DEVELOPED IN A WORKING FLUID. A DIE AND PRESSURE CHAMBER ARE BROUGHT TOGETHER WITH THE WORK DISPOSED BETWEEN THE TWO AND RESTRAINED FROM MOVEMENT BY CLAMPING ENGAGEMENT DURING THE MOVEMENT OF THE DIE AND CHAMBER. THEREAFTER, ONE OR MORE INTENSE PRESSURE WAVES SUCH AS SHOCK WAVES ARE GENERATED IN THE WORKING FLUID IN THE CHAMBER AND ARE OPERATIVE TO CAUSE THE WORK MAY BE PREDETERMINATELY DEFORM AGAINST THE DIE. THE WORK MAY BE DEFORMED AS THE RESULT OF A SINGLE PULSE OF INTENSE PRESSURE WITHIN THE WORKING FLUID OR BY GENERATING A PLURALITY OF PULSES, ONE AFTER THE OTHER, SUCH THAT EACH PULSE CAUSES AN INCREMENTAL DEFORMATION IN THE WORK THE SUM OF WHICH DEFORMATIONS INVOLVES PREDETERMINATELY SHAPING THE WORK TO CONFORM TO THE SURFACE OF THE DIE IN A PROGRESSIVE MANNER.

1 March Z, 1971 J. H. LEMELSON 3,566,645

, METHOD AND APPARATUS FOR PRESSURE WORKING MATERIALS Filed March 5, 1968 g MULTl-CIRCUlT INVENTOR. gEROME H.LEMELSON United States Patent 3,566,645 METHOD AND APPARATUS FOR PRESSURE WORKING MATERIALS Jerome H. Lemelson, 85 Rector St., Metuchen,N.J. 08840 Continuation-impart of applications Ser. No. 668,561,

June 27, 1957, and Ser. No. 501,395, Oct. 22, 1965,

now Patent No. 3,371,404. This application Mar. 5,

1968, Ser. No. 710,518

Int. Cl. B21d 26/06 U.S. Cl. 72-56 9 Claims ABSTRACT OF THE DISCLOSURE A method and apparatus are provided for forming material such as sheets and plates by means of intense pressure developed in a working fluid. A die and pressure chamber are brought together with the work disposed between the two and restrained from movement by clamping engagement during the movement of the die and chamber. Thereafter, one or more intense pressure Waves such as shock waves are generated in the working fluid in the chamber and are operative to cause the work to predeterminately deform against the die. The work may be deformed as the result of a single pulse of intense pressure within the working fluid or by generating a plurality of pulses, one after the other, such that each pulse causes an incremental deformation in the work the sum of which deformations involves predeterminately shaping the work to conform to the surface of the die in a progressive manner.

Other aspects of the invention include the injection of certain materials into the pressure chamber prior to or during the process of generating intense pressure pulses therein which pressure is operative to cause said materials to react on, combine with or coat the surface of the work.

RELATED APPLICATIONS This is a continuation-in-part of copending applications Ser. Nos. 668,561 and 501,395, now Pat. No. 3,371,404, which were respectively filed on June 27, 1957, and Oct. 22, 1965, the former being entitled Wave Generating Apparatus and the latter entitled Method of Simultaneously Cladding and Deforming Material by Intense Pressure.

SUMMARY OF THE INVENTION This invention relates to an apparatus and method for working material such as a sheet or a plate by means of intense pressure, although it is not necessarily confined to sheet materials as other irregular sheets may be similarly worked.

Various methods and apparatus for forming materials such as metals, polymers or ceramics, to predetermined shapes are known in the art and include such techniques as die-pressing, stamping, bending, stretch forming, spinning and the use of explosive materials disposed directly against the surface of a member to be formed and operative to explosively deform same against a die. While these techniques are all suitably used to advantage, nevertheless they exhibit certain limitations with respect to the material being formed, equipment operation and cost, direct labor requirements and the characteristics of the shaped article. Explosive forming has been applied with success to form heavy plates of difficult to form metal but suffers a number of shortcomings as it requires an explosive charge, substantial labor to prepare for each forming operation and cycle time required to form each piece.

Accordingly, it is a primary object of this invention 3,566,645 Patented Mar. 2, 1971 to provide a new and improved apparatus and method for working material by means of high pressure waves such as shock waves generated in a fluid in a confined volume.

Another object is to provide a method and apparatus for forming sheet material by intermittently applying a plurality of intense pressure pulses to said sheet so as to progressively deform same into or against a die and simultaneously work the material being deformed.

Another object is to provide an apparatus for forming sheet metal by fluid pressure means, which apparatus is automatic in its operation and does not require manual labor to set up or feed the sheet metal.

Another object is to provide an apparatus for generating intense pressure waves at a predetermined cycle frequency and for using such waves in such a manner as to perform one or more operations on a work piece such as predeterminately forming said work piece, surface eroding, coating or cladding articles disposed in direct or indirect alignment with a medium through which said waves are transmitted.

Another object is to provide a new and improved method for causing a difficult to form sheet or plate of material to conform to a die by generating a plurality of high-pressure pulses or shock waves in a fluid medium and transmitting the forces thereof to said sheet material to incrementally deform the material and cause it to conform to the surface of the die.

With the above and such other objects in view as may hereafter more fully appear, the invention consists of the novel constructions, combinations and arrangements of parts as will be more fully described and illustrated in the accompanying drawings, but it is to be understood that changes, variations and modifications may be resorted to which fall within the scope of the invention as claimed.

In the drawings:

FIG. 1 is a cross sectional view of a sheet forming apparatus employing high-intensity pressure waves such as shock waves and operative to perform other functions as well, and

FIG. 2 is a sectional view of a fragment of an apparatus similar to FIG. 1 for having modifications thereto.

FIG. 1 shows apparatus for shaping metal sheet or plate by means of one or more high-pressure or produced shock waves. By clamping sheet material such as metal or plastic sheet in a die having a cavity, protrusion or otherwise shaped portion disposed adjacent a first face of said sheet, and directing one or more high-intensity pressive waves such as shock waves against the other face of said sheet, the forces due to said intense pressure or waves directed against the unsupported portion of the sheet may be operative to cause said sheet to deform against and conform to the walls of said die cavity or protrusion. Depending on the intensity of the pressure or shock waves, the sheet may be rapidly or gradually worked or deformed against the die to cause said sheet to conform to the forming section of the die. Materials normally difficult to form by conventional press means such as exotic metals and alloys may be so worked or formed.

In FIG. 1 a fluid pressure forming apparatus 10 is provided comprising a reaction chamber 12 which may form part of or terminate a shock tube in which high pressure or shock waves are generated by suitable means such as the arcing of high intensity electrical sparks discharged across said chamber, intermittent explosions generated therein by chemical or electrical means, or rapid combustion caused by intense radiation directed into the chamber. Reaction chamber 12 may also be provided in any suitable configuration or shape and may include means for generating shock waves of a desired intensity. Such waves or pressure pulses may be generated singly or in rapid succession in a manner to reinforce each other. The chamber or tube 12 is provided with means 14 for raising and lowering said chamber against a bed 13 comprising a rigid platen or bed 15 to which is secured a die 16 shown having a cavity 17 against which a member 18 such as a sheet of metal is to be deformed by pressure and heat applied to one face thereof. The cavity-containing die 16 may be replaced with a flat platen if it is desired to work the surface of the member 18 such as byflattening or straightening said member, heat treating or workhardening same. It is noted that by placing material such as metal powders or abrasive grit particles on the surface of member 18 they may be worked into or bonded on said member 18 or may be caused to abrade said surface by the action of the shock waves thereon. A steel die (not shown) placed on Work member 18 and free to move towards the die 16, may also be urged by the impact pressure of the shock waves generated in chamber 12 to shape or penetrate the surface of sheet 18. Such a die may be slidably engaged in the bore of chamber 12 or by guides supported by bed 15 and may, when intersected by shock waves directed down chamber 12, coact with the die 16 to deform, emboss or cut the sheet 18. Means 14 for raising and lowering the chamber 12 is provided and comprises a plurality of hydraulic or air cylinders and 21 which are supported on the frame 19 of the press, the rams 20, 21' of which cylinders engage a flange 22 of the chamber 12 and preferably are attached thereto for cooperating in raising and lowering the chamber 12 and forcing its lower rim into clamping engagement against the press bed and/ or work 18. In FIG. 1, a circumscribing ridge-like protrusion or lip 23 projects from the open end-face 12' of the chamber and is adapted to be forced against the sheet 18 to effect a fluid pressure seal therewith. The lip or ring-shaped rim 23 may be replaced by a sealing ring such as a metal seal or O-ring to effect such a circumscribing pressure seal. Upon clamping engagement of the end face 22 of the chamber 12 against the press bed 15, shock waves may be produced as described by exploding chemicals in said chamber 12 to effect the desired work forming, coating or cutting action on the member 18.

If work member 18 is metal or other thermoplastic material, it is noted that, by producing a plurality of intermittent shock waves in the chamber volume 12V, sufficient heat from said shock waves may be transferred thereto to raise its temperature a degree whereby it will become softened or rendered malleable and more easily workable by the forces of the pressure or shock waves directed thereagainst. The degree of softening or increase in workability will be a function of the intensity of the shock waves generated, their characteristics, frequency and the physical characteristics as well as dimensions of the material 18 being worked or formed. By producing fluid pressure in excess of 10 psi. or shock waves of an intensity greater than Mach 2 and at a frequency in excess of 25 per second, most plastic or thin metal non-ferrous sheets may be formed or worked as described. As the intensity and frequency of the shock waves are increased, the time required to work the member 18 will be decreased. Many materials not easily formed or worked by conventional means may be formed using fluid pressures or shock waves in excess of Mach 3 produced at frequencies in excess of per second. Two sheets of the same or different metals may replace the single sheet 18 of FIG. 1 and may be simultaneously worked or clad together by the action of the intense shock waves so generated.

Notation 25 refers to one or more conduit or nozzle inlet means connected to the shock tube 12 for blowing or otherwise injecting a fluid such as one or more liquids or fluent particles into said tube and/or against the surface of the sheet or plate 18 prior to while the shock waves are directed thereagainst. The heat and pressure of said shock waves may be used in coaction with the fluid or material injected through conduit 25 to effect one or more physical and/or chemical reactions on member 18. Material injected through duct .25 may be used to perform one or more of the functions of abrading or roughening the surface of the work, coating or cladding said surface (which may or may not have been previously abraded by said action) with suitable particulate coating or sheet material during or just prior to or after the forming action. A chemical or other physical change may also be effected on member 18 such as one operative to effect softening or cleaning its surface, etching or other action which is enhanced or effected by the temperature and pressures of the shock waves directed thereagainst. In certain of these fabrication or processing actions, the die 16 may be replaced by a flat platen for surface coating, abrading or otherwise processing sheets, plates or otherwise shaped solids with shock waves and chemicals while said shapes are held stationary or conveyed through the chamber.

Flexible conduit 25 which terminates at a small opening 25' provided at the lower end of the side wall 12" of the elongated reaction chamber 12 may also be utilized for admitting a working fluid to the volume 12V of the reaction chamber 12 which Working fluid may be utilized as a transmitting means for the shock waves generated in the upper portion of the chamber and/or may contain one or more explosive chemicals for generating said shock waves. Conduit 25 may also be used to inject particulate material into the chamber for the purposes described. In one form of operation of the apparatus 10, the working fluid may comprise air or an inert gas in which shock waves are generated and transmitted to th work piece from the wave generating means. In other forms of the invention, liquid such as water or oil may be pumped through conduit 25 from a reservoir supply 26 thereof connected to said conduit after the chamber 12 has been removed to a downward position to effect a fluid pressure seal between the circumscribing lip 23 and the upper surface of the sheet or plate 18. After the sheet or plate 18 has been worked or deformed to conform the wall of the cavity 17 of die 16, automatic control means to be described are operated to either control lineal actuator cylinders 20 and 21 to either lift the chamber immediate, if the working fluid contained therein is air, or to effect operation of the pump 26 for removing liquid working fluid from volume 12V prior to controlling the operation of cylinders 20 and 21 to lift said chamber. Notation 16 refers to a passageway in the wall of the die 16 leading to cavity 17 which may be utilized for evacuating air therefrom either prior to the wave forming action or as the result of deformation of sheet 18 into said cavity.

As stated, shock wave cladding or coating of metal sheet or plate material may be effected by disposing a sheet or particulate material to be coated onto another sheet, plate or other shape and subjecting same to one or more intense shock waves operative to heat and compression bond the two materials together. Sheet metal such as aluminum, titanium, molybdenum may be clad to other metal sheet such as steel by clamping both between the end of the combustion chamber or shock tube as described or by otherwise clamping or holding the two together during generation of the one or mor shock waves necessary to effect cladding. Material in particulate form or as a coating may be disposed against one of the two sheets to abut the other sheet and partake in the cladding or coating operation to facilitate or effect same.

The mean illustrated in FIG. 1 for generating a succession of shock waves in the volume 12V of the reaction chamber 12 include a plurality of pairs of electrodes defined by notations 27, 28 and 30, 31 which are illustrated as being disposed in respective diametrically opposite portions of the upper end 12a of the chamber 12 and across which high intensity electrical discharges or sparks are generated which are operative to generate shock waves. Each shock wave so generated has a first component which travels down chamber 12 in the fluid therein and intersects the surface of the work piece 12 exposed thereto. A second component of the shock wave travels up the chamber and reflects off the spherical or parabolic end wall 12b of the chamber and thence downward in the direction of the work.

One or more additional pairs of electrodes such as the illustrated electrodes 30, 31 may be operative to generate shock waves interposed between those generated by the upper electrodes 27 and 28 and, in a preferred form of the invention, are all generated in timed relation to those generated by the other electrodes so as to amplify or reinforce the resultant shock wave resulting in a greater force being applied to the work pieces. Further pairs of similar electrodes may also be provided and so energized as to increase the reinforcement or amplification of one or a group of shock waves traveling along the tube toward the work to provide the desired force and temperature for operating on and deforming said work. As stated, in a preferred form of the invention, the shock wave not only transmits a force of substantial magnitude to the work which is operative to deform, clad, heat treat or otherwise physically atfect the work or the material thereof in a predetermined manner to improve same, but also transmits substantial heat to the surface of the work which may be utilized to render same more easily worked by the force of the shock wave.

The reaction chamber 12 may be produced of a material which is not electrically conducting such as a ceramic or may be lined or coated therewith on the inside for serving a plurality of functions including protecting the main chamber Wall from heat distortion and corrosion and for insulating the electrodes across which high intensity spark discharges are generated. In FIG. 1, the electrodes are each shown supported in a tubular member 29 which is held in a boss portion 12 extending from the reaction chamber and serves not only to insulate said electrode but to protect same from the vibration and shock. The formation 29 may be made of any suitable ceramic or high temperature polymer. A suitable material from which the entire wall or lining of the reaction chamber 12 may be fabricated in so-called Pyroceram, a shockresistant ceramic material manufactured by the Corning Glass Works of Corning, NY. If the entire wall is fabricated of such a material or if such a material lines the wall of a metal reaction chamber the interior surface of the ceramic may be coated or lined with a further material such as silicone carbide, boron nitride, aluminum oxide, tungsten carbide, titanium carbide or the like. These materials may be also utilized to directly coat the inside of a steel or stainless steel reaction chamber wall for heat resistance and electrical insulation purposes.

Means shown in FIG. 1 for controlling the operation of the various described mechanical and electrical devices comprise a master controller 44 such as a digital computer or multi-circuit sequential controller having a plurality of outputs 45 extending to controls for the various described servo devices as well as to means for generating and controlling the discharge or electircal sparks across the chamber wall for generating shock waves within the apparatus. In its simplest form, the controller 44 may comprise a multi-circuit, self-resetting timer which is adjusted to effect the following operations by gating signals or power to the devices to be described. The first signal generated by controller 44 closes a bi-stable switch 39 connecting a source of line current PS to energize a high voltage generator 38. The generator 38 is connected to a multi-pole switch 35 having a plurality of outputs 36 extending to the positive electrodes 28 and 31 of the described electrode pairs. Switch 36 is operated when a wiper arm thereof 37 or other suitable contact making means is operated by a servo 40 such as a constant speed, controllable motor 40 having a control input 41 which itself is controlled by a signal or signals generated by the controller 44. Lines 32 and 33 extend to positive electrodes 28 and 31 whereas a ground line 34 extends to electrodes 27 and and connects to the source of high voltage through switching device 35. Thus the device 35 is operated to generate the desired number of shock waves in the volume 12V for a predetermined period of time which occurs during a predetermined interval in a controlled production cycle. Other outputs 45 from the controller 44 extend to forward and reverse control inputs FR of control means 42 which are operative to projecting and retracting the shafts 20' of actuators 20 and 21 which lower and raise the reaction chamber 12. Other outputs of the master controller 44 extend to controls F, S, and R for operating, stopping and reversing the described fluid pump 26 for admitting and removing fluid to the chamber 12V for the purposes described. Still other outputs of the master controller 44 extend to forward and reverse controls F and R of a servo operating a device 43 for transferring the work piece 18 to the die 16, prepositioning same and, when controller R is operated, for removing said work piece from said die and replacing same with a new work piece.

Thus master controller 44 is preprogrammed or adjusted to affect the sequence of operations which include the operation of transfer device 43 to preposition a work piece 18 across the face of die 16; operation of actuators 20 and 21 to move the chamber 12 downwardly to sealingly compress the lip or seal 23 thereof against the work 18; operation of pump 26 to admit fluid or particulate material (in those production operations where applicable) the chamber 12V; connection of a source of power PS to the high voltage generator 38; operation thereafter of the switching device 35 to generate one or more high voltage sparks across the combustion chamber by energizing one or more of the described pairs of electrodes; reverse operation of pump 26 (where applicable) to remove fluid from volume 12V; reverse operation of fluid cylinders 20 and 21 to lift the chamber 12 to clear the Work piece; operation of transfer device 43 to remove the formed Work piece from the surface of the die; and further operation of transfer device 43 to replace the old work piece with a new work piece. Not mentioned in the above cycle, though applicable in certain instances, would be the application of suction pressure to the line 16 extending to the die cavity volume 17 following the step of engaging a sealing lip 23 of chamber 12 against the surface of work piece 18.

It is noted that the apparatus of FIG. 1 may be operated to receive work in other forms than individual pieces of plate or sheet. For example, articles of a suitable shape may be disposed within the chamber against a flat platen or block replacing die 16 or against the upper surface of the plate 18 for the purposes of coating, abrading or eroding same or effecting the welding of a plurality of the components disposed within the chamber by pressure and heat applied as a result of the generation of one or more shock waves therein. For example, a plurality of components may be secured or otherwise predeterminately positioned on plate 18 to be welded to each other and/ or to the plate itself.

FIG. 2 illustrates modifications to the apparatus of FIG. 1 permitting the feeding of material to the wave forming apparatus wherein said material is in the form of a continuous sheet or plate. The material 18' is shown being fed to the reaction chamber 12 along an input conveyor 46 which includes a plurality of cooperating powered rolls 47, 48 powered by a servo (not shown) which is controlled by master control 44 to position new lengths of said sheet in alignment with the forming die 16. The sheet 18 is shown deformed at portion 18" to the cavity of the die 16' as the result of pressure or wave action within the chamber 12; The sealing lip 23 of FIG. 1 has been modified in FIG. 2 to define, in addition to means for sealing engaging that portion of the sheet extending across the chamber 12, further means in the form of a sharp edge 23 or knife operative to die cut a predetermined portion of said sheet including the deformed portion 18" thereof. Notation 52 refers to one or more resilient or rigid wear resistant inserts secured to die block 16 which cooperate with the knife edge or sharp rim .23 extending from the flange 22 or end of the chamber 12. Thus, prior to or immediately after forming the central portion 18" of each portion of sheet disposed across the die 16, chamber 12 is compressively forced by the operation of the actuators 20 and 21 to die cut sheet 18' into individual sections which include a portion thereof which is worked or formed to shape by means of the pressure or wave action generated in the volume 12V.

After the portion of sheet 18 has been shaped or otherwise predeterminately worked, the master controller 44 generates signals for lifting chamber 25 and/ or retracting the die 16 to permit the article or deformed portion of sheet 18 to be removed from the die. Such removal may be effected by operating a take-off conveyor 49 which includes a plurality of power operated rollers 50 and 51 engaging the border areas of the deformed portion of the sheet 18' for removing same from alignment with chamber 12 provided that said deformed portion is not totally severed from that portion of the sheet driven by conveyor 49. A blast of air ejected through passageway 16 in the die may also be used to blow the sheet or severed portion thereof out of the die cavity. The sequence of actions controlling the modified form of the wave generating apparatus of FIG. 2 which are described in the description of FIG. 1, are also assumed to be controlled by master controller 44 where applicable.

While the apparatus hereinbefore described may employ a plurality of shock waves generated in the confined liquid or gas disposed in the reaction chamber to predeterminately deform, weld, clad, erode, coat or otherwise process material such as sheet metal or other shapes of metal or non-metallic materials, it is noted that one or a plurality of successively generated shock waves or pressure pulses of lesser intensity may be formed within the reaction chamber by other means. For example, the sudden generation of an intense beam of radiant energy such as that generated by an electron gun or a so-called laser may be directed into the liquid or gas defining the working fluid through a transparent portion of the wall of the chamber such as a high temperature glass or ceramic window or wall itself and may be utilized to generate said shock waves by the sudden transfer of heat thereto or to increase the fluid pressure by heating the gas or vaporizing a portion of the liquid. Chemical combustion or explosive reaction means employing a solid, particulate, gaseous or liquid combustible or explosive chemical or chemicals may also be continu- I ously or intermittently fed to the reaction chamber in a controlled manner by a conveying means operated or controlled by a servo which is controlled by the described master controller 44 and may be rapidly burned or exploded by a controlled spark, intense laser or electron beam, radio frequency energy or other suitable means to generate one or more pressure waves within the chamber for the purposes described.

The apparatus of FIG. 2 may be modified to effect a plurality of operations on work other than the deformation of sheet material by shock wave means as described. For example, the driven sheet 18' may comprise a conveyor belt of suitable temperature resistant material and the die block 16 replaced by a flat bed or platen to support the belt within the reaction chamber. Material such as particulate material, articles or containers of material to be processed may be disposed at spaced intervals on the belt such that the intermittent movement of the belt will be operative to dispose each batch of material, articles or article in alignment with the chamber volume 12V so as not to prevent the rim 22 of the chamber from closing against the upper surface of the belt to enclose the reaction chamber volume prior to the generation of shock waves therein to react on said material or articles. In another form, the chamber 12 may be 8 disposed with its end always positioned off the conveyor or belt 18' so that shock waves generated within the chamber will pass from the end thereof and intersect the work for the purposes described. The apparatus of FIG. 2 may also be modified to elfect the continuous or intermittent coating of a sheet with a material introduced into the chamber as described or conveyed along with sheet 18 into alignment with the open end of the reaction chamber which may be operated either by engaging the conveyor or disposed thereoff as described to heat and subject the work to intense pressures. Two sheets of metal may be brought together and fusion bonded or welded together by the action of a plurality of shock waves generated while the chamber 12 is intermittently closed against the sheets as in FIG. 2 or disposed thereabove, a flat surfaced block similar to die 16" without the cavity or a drum serving to buck and support the sheets during the reaction of the shock waves thereagainst; or two such sheets may be disposed between the aligned rims or flanges of two reaction chambers, each being operative to direct shock waves against opposite faces of the abutting sheets to weld or fusion bond the sheets together. Such shock Waves may be generated in the aligned chambers so as to simultaneously intersect opposite faces of the abutting sheets and fusion bond or weld them together. Metal, ceramic or plastic sheets or combinations of these materials may be so laminated or welded together. Continuous coating of a sheet of metal with ceramic material or plastic material or a metal may be effected by introducing the coating material in particulate form either onto the surface of the sheet before it comes into alignment with the end of the reaction chamber or shock tube 12 or by introducing said coating material into said chamber as described to be carried by the shock waves against the sheet while it is stationary as in FIG. 2 or in movement thru or past the end of the chamber. Tungsten, titanium or zirconium carbide, boron or aluminum nitride, aluminum oxide, silicon carbide and other ceramic materials may be coated onto metal plate or sheet on a continuous or intermittent basis as described by the action of shock waves as described.

Two sheets of material such as metal or metal and ceramic may be bonded together by still another technique utilizing apparatus of the type provided in FIGS. 1 and 2. By disposing a suitable particulate material, plating or coating against the surface of one of the sheets which is thereafter brought into abutment with the other sheet, and thereafter disposing the abutted sheets in the locations of the sheet materials of FIG. 1 or 2 and reacting on same with one or more shock waves, the intermediate particulate or coating material may be operative to melt and fusion bond or otherwise attach to both sheets to weld the two together. Shock wave or explosive welding, brazing or molecular bonding of two sheet materials may thus be effected where the direct cladding of two sheets may not be suitable. Coating of molybdenum on steel for example, by the described shock wave means or other suitable means prior to disposing the coated surface against a material such as a sheet or particulate material to be clad thereto, may be operative to provide a superior clad assembly thereof with another steel or aluminum sheet. Both ferrous and non-ferrous metals, ceramics and thermoplastic polymers may be laminated or clad or coated together by providing suitable intermediate material on one of the sheets or articles prior to subjecting the combined materials or sheets to the action of the shock waves.

It is noted that the apparatus of FIGS. 1 and 2 may be operative to clad and deform two or more sheets against a die by abutting said sheets with or without an intermediary material disposed therebetween, prior to generating said shock waves.

What is claimed is:

1. A work processing apparatus comprising in combination:

(a) die means operative to form sheet material and the like,

(b) a press bed including means for supporting said die means,

(c) fluid confining means including a pressure chamber and a working fluid within said chamber,

(d) means for relatively moving said die means and said pressure chamber to bring the two into and out of operative relationship, and to form when said die means and pressure chamber are in operative relationship, and enclosed volume adjacent material disposed against said die means,

(e) means for engaging material to be formed against said die means within said pressure chamber so as to permit said material to be worked by the fluid confined in the chamber,

(f) means for generating intense pressure within said chamber and applying said intense pressure through said fluid to said sheet material,

(g) first control means for said moving means,

(h) second control means for said means for generating intense pressure, and

(i) automatic control means operatively connected to said first and second control means for causing said die means and said chamber to be brought into operative engagement with each other, then to cause said pressure generating means to generate intense pressure in said working fluid for reacting directly against said sheet material and causing predetermined changes in the shape of said sheet material by deforming said sheet material against said die means, and thereafter to cause separation of said chamber and said die means to permit removal of the deformed sheet material from between the two.

2. Apparatus in accordance with claim 1 including means for feeding sheet material to be operated on between said press bed and said chamber and into alignment with said die means, a portion of said chamber being shaped and operative for clampingly engaging said sheet material against said die means to define said enclosed volume, control means for said sheet feeding means, said feeding means control means being operatively connected to said automatic control means, said automatic control means being programmed in its operation to cause sheet material to be fed between said press bed and said pressure chamber when the two are separated from each other and to cause movement of the die and chamber into operative relationship with each other.

3. Apparatus in accordance with claim 1, said sheet material comprising a sheet of metal, said means for generating intense pressure in said working fluid being operative to cause said sheet of metal to permanently deform against said die means and substantially conform to the surface thereof.

4. Apparatus in accordance with claim 1, said work comprising a sheet of thermoplastic polymeric material, and means for rendering said thermoplastic material in a soft, thermally deformable condition when disposed between said pressure chamber and said die means to cause the sheet to conform to the surface of said die means.

5. Apparatus in accordance with claim 2 including means at the end of said pressure chamber for effecting a fluid pressure seal between the end of the chamber and said sheet material when said die and chamber are brought into operative relationship with each other.

6. Apparatus in accordance with claim 1, said means for generating intense pressure comprising pressure pulse generating means for generating an intense pressure pulse in the working fluid.

7. Apparatus in accordance with claim 6, said means for generating said intense pressure pulse comprising spark discharge means disposed in said chamber and controlled by said master control means to generate a single shock wave in said fluid which shock wave is operative to deform said sheet to conform to said die.

8. Apparatus in accordance with claim 1, said automatic control means being operative to control said means for generating intense pressure within said working fluid to intermittently generate a series of pressure pulses each of which is operative to deform said work a predetermined degree whereby said work is made to conform to said die by incremental degrees of deformation in said sheet.

9. Apparatus in accordance with claim 8, said automatic control means being operative to control said means for generating intense pressure Within said working fluid so as to intermittently generate intense shock waves in said chamber for intermittently operating on and deforming said sheet material disposed therein.

References Cited UNITED STATES PATENTS 3,194,047 7/1965 Eggert, Jr. et a1. 72-349 2,405,714 8/1946 Ryan 72-56 2,559,227 7/1951 Rieber 340-12 2,714,563 8/1955 Poorman et a1. 72-56 3,027,791 4/1962 Early et a1. 72-56 3,228,222 1/1966 Maier 72-56 3,289,447 12/1966 Amini et al. 72-56 3,452,565 7/1969 Cadwell 72-56 FOREIGN PATENTS 742,460 12/1955 Great Britain.

RICHARD J. HERBST, Primary Examiner 

